1. The ocean covers more than 70% of the Earth's surface. (True)
2. The deepest part of the ocean is the Challenger Deep, located in the Mariana Trench. (True)
3. The Sargasso Sea is located in the northern Atlantic Ocean and is known for its floating mats of seaweed. (False. It is located in the western Atlantic Ocean.)
4. The Great Barrier Reef is a large underwater coral reef located off the coast of Africa. (False. It is located off the coast of Australia.)
5. The largest ocean on Earth is the Pacific Ocean. (True)
6. Blue whales are the largest animals on Earth. (True)
7. The ocean is home to over 250,000 known species of plants and animals. (True)
8. The ocean is a major source of oxygen for the Earth's atmosphere. (True)
9. The ocean is getting warmer due to climate change. (True)
10. The ocean is a major source of food for humans. (True)